When you buy a 295 tire you have to expect some type of noise, some brand of tires are louder than others.
There are alot of other factors also for MPG.
Depending on your location, Winter gasoline is used and that may drop a little mpg.
The powerboost is electric so cold weather is not the most...
i have the same car, at stock it rides like my mercedes GLS. Now that i upgraded to bilsteins 6112 and 5140 rear with hellwig sway bar, it drives like a sports car
i also have a 295 60 20 nitto ridge grapplers. Although i did see a drop in about 1-2 mpg, i still think its still pretty good. I also have a pedal commander that i set to eco for daily driving and it tends to stay in electric a little longer after i get it up to at least 25 mph.
wrapped it gloss black, base on installer it was a tedious task for the front grill.
bilstiens 6112 front and 5140 rear with hellwig sway bar
Vossens 20 inch with+15 offset
Nitro ridge grapplers 295 60 20
Drove about 1k miles and just added the pedal commander today . I was able to set on eco settings to stay in electric easier and the sport and city option was immediate response on the throttle